Results from a new study raise concern that air pollution could be harming unborn babies.

Scientists from Queen Mary University of London in England announced they found pollution particles in the placenta of pregnant women for the first time ever.

“Our results provide the first evidence that inhaled pollution particles can move from the lungs into the circulation and then to the placenta,” said Dr. Norrice Liu, a pediatrician.

“We do not know whether the particles we found could also move across into the fetus, but our evidence suggests that this is indeed possible,” Liu said.

The finding raises concern that the polluted particles are reaching unborn babies and potentially endangering their health.

“We also know that the particles do not need to get into the baby’s body to have an adverse effect, because if they have an effect on the placenta, this will have a direct impact on the fetus,” Liu added.

The study looked at five pregnant women scheduled for C-section births in London. All five had healthy babies, uncomplicated pregnancies and deliveries and were non-smokers. Researchers examined the placenta after the babies were born.

The scientists found tiny carbon particles in the placenta which they believe entered the women’s bloodstream when they breathed in polluted air.

London is one of Europe’s most polluted cities and air pollution has become an increasing concern in the city.

Last August Shirley Rodrigues, London’s deputy mayor, said air pollution had reached a “tipping point”.

“It’s not only (because of) the thousands of deaths brought on early, but also the pernicious, chronic illnesses that are costing the health service a lot of money. It is affecting quality of life,” she added.

To find the carbon particles, the scientists looked for immune cells called placental macrophages which absorb dangerous particles including pollution.

They found 3,500 macrophage cells. Of those cells, they found 60 cells that contained a total of 72 small black areas which they believed were pollution particles.

Next they looked at two of the placentas in more detail and found the black areas did contain the carbon pollution particles.

“We were not sure if we were going to find any particles and if we did find them, we were only expecting to find a small number of placental macrophages that contain these sooty particles,” Liu said. “This is because most of them should be engulfed by macrophages within the airways.”

The researchers presented their findings at the European Respiratory Society last Sunday. Mina Gaga, president of the European Respiratory Society, said the study confirmed earlier studies.

“Previous research shows that pregnant women living in polluted cities are more prone to pregnancy issues such as restricted fetal growth, premature birth and low birth weight babies,” Gaga said.

“This new research suggests a possible mechanism of how babies are affected by pollution while being theoretically protected in the womb,” she added. “We need stricter policies for cleaner air to reduce the impact of pollution on health worldwide.”